Contributions from the University of Michigan Herbarium.University of Michigan. University Herbarium.textseriesAnn Arbor :University Herbarium, University of Michigan,1939-1939EnglishBiological abstracts | 0006-3169Publication suspended 1943-1965.Occasional articles in Spanish.BotanyQK1.C6567http://www.biodiversitylibrary.org/bibliography/124111757325